Electrical connection means



I 5 H. A. DOUGLAS v 2,

ELECTRICAL CONNECTION MEANS v MW ATTORNLTS I a W 2 v/ M M H w Patented Jan. 17, 1939 UNITED STATES ELECTRICAL CONNECTION MEANS of Indiana Application June 5, 1935, Serial No. 25,116

' 2 Claims. (01.173-328) My invention relates to electrical connection means, and more particularly to electrical terminal posts adapted for the reception of plug conductor terminals of the snap type, and the principal object of my invention is to provide new and improved electrical connection means of that type. In the drawing accompanying this specification and forming a part of this application, I have shown for purposes of illustration, one form '-which my invention may assume, and in this drawing:

Figure 1 is an elevational view of a terminal post embodying my invention, mounted on a base fragmentarily shown, the post being partly in vertical section,

Figure 2 is a section taken on the line 22 of Figure 1, looking in. the direction of the arrows,

and I Figure 3 is a section taken on the line 3-3 of Figure 1, looking in the direction of the arrows, aplug conductor terminal; cooperable with the terminal post, being added.

In the illustrated embodiment of my invention a terminal post ii] comprises a metallic solid body portion H, here shown as of square cross-section through the lower part l2 of its length, the upper part l3 being generally frusto-conical.

The body portion I l is providedwith a chamber i i adapted to receive a detent means l5. 'The chamber it may be formed in part by drilling a cylindrical longitudinally extending hole into the body portion thereby forming a longitudinal bore it. The chamber I4 communicates with a transverse bore or aperture H which may be formed by drilling through the body portion l i from one side through the other. The longitudinal bore 16 of the chamber I4 is put in communication with the transverse aperture H by means of a longitudinally extending communicating bore l8 concentric with the bore it but of lesser diameter than the bore 56. The communicating bore I8 may be formed as a continuing operation of the formation of the bore l 6, and the transverse bore I! may be formed subsequently to formation of the bores it, It.

The detent means l5 here shown comprises a generally hemispherical portion 19 provided with a circular flange 20. The flange 20 fits with a sliding fit in the bore 16. The detent means i5 is desirably also provided with a projection or shank 2i, here shown as of cylindrical form with a rounded end 22. The shank 2! is concentric with the flange 2t and with the hemispherical portion i9, and extends away from the flange in a direction opposite from that of the hemispherical portion 19. The detentmeans I5 is disposed in the chamber it of the body portion of the post so that the flange 20 is seated on an annular shoulder 23 formed at the lower end of the longitudinal bore It. The flange 20 also serves as a seat for one end of a helical spring 2 5, disposed about the shank 2!, for biasing the flange 20 against the shoulder 23. The spring 25 is shown as so proportioned that its inner periphery and its outer periphery fit with a sliding fit the shank 2| and the bore I6 respectively. The other end of the spring 24 may abut a seat 25 here shown as formed by closing in the upper marginal portion 25 of the metal surrounding the longitudinal bore It, the seat 25 so formed being annular and in this instance margined on its inner periphery by the axially downwardly extending free end of the portion 26. The formation of the seat 25 is facilitated and crushing of the metal surrounding the bore H5 is prevented-by making the end part l3 frustro-conical. The detent means l5 may be made of a single piece of solid metal.

The spring 24 biases the detent means I5 to a position in which the hemispherical portion l9 projects a predetermined amount into the transverse aperture l'l.

The terminal post ll] may be mounted on a support 21 in any desired manner, the post it! being here shown as having a portion 28 of reduced diameter passing through an aperture 29 in the support 21, the end 30 of the reduced por-v tion being spread, in any suitable way, over the underside of the support 2? to tightly hold the post to the support. The end 38 may serve as a contact for a switch member (not shown) or the post may be connected to an electrical conductor in any suitable manner.

The terminal post I0 is adapted to cooperate with a plug conductor terminal, such for example as shown in Figure 3, having a cylindrical portion 3! provided with an annular furrow 32 and a frustro-conical end 33. The plug conductor terminal may be fastened to a conductor 35 disposed therein by swedging, as indicated by swedge indentations 3 5. When the plug conductor terminal is inserted into the aperture the frustroconical end 33 acts as a cam against the hemispherical portion 89, thereby moving the entire detent means 55 longitudinally against the bias of the spring 24. Further inserting. movement causes the hemispherical portion is to snap into the annular furrow 32.

Inasmuch as the spring 24 is related to the shank 2i and to the bore it as hereinbefore described, the shank 2! and spring 24 and bore it cooperate to hold the detent means in axial alinement with the communicating bore I8. The detent means is thereby prevented from cocking over and is guided for approximately longitudinal movement only. The construction of the detent means 15, having the shank 2|, also is adapted for rapid automatic picking up from bulk of the detent means for assembly with terminal posts.

It will be evident that I have provided a terminal post, adapted for the reception of plug conductor terminals of the snap type, which can be so constructed as to provide a gauge plane or point, the shoulder 23, which can be used as a gauge plane or point in drilling the transverse aperture I1, thereby accurately relating the transverse aperture to the shoulder 23. At the same time the shoulder 23, accurately and definitely positions the flange 20, and therefore the hemispherical portion 19, so that the hemispherical portion l9 extends transversely into the transverse aperture H a predetermined amount. Moreover, the flange 20, in cooperation with the bore I6 centers the hemispherical portion H) in the communicating bore I8.

It will be further evident that gauging or positioning of the detent means l5, by engagement of the under side of the flange 20 with the shoulder 23, and by gauging of the outer periphery of the flange 20 in the bore l6, enables the communicating bore l8 to be made considerably larger than the diameter of the hemispherical portion 19 so that burs or fins which may be produced in the machining operation for forming the bores l1, It, for example, will not interfere with the detent means l5, nor with the plug conductor terminal. The communicating bore l8, and the transverse aperture 11, are customarily drilled at different times, and therefore the last bore drilled will result in a bur or burs (not shown) at various places along the line of intersection 36 of these bores, The relation between the diameter of the communicating bore i8 and the diameter of the hemispherical portion l9 of the detent means I5 is so selected that any bur or fin formed at the intersection between the communicating bore l8 and the transverse aperture i! will not interfere with the movement of the hemispherical portion into or out of its position shown in Figure'l, in which the flange 2B is seated on the shoulder 23, and which position the detent means I5 should assume when no plug conductor terminal is inserted in the transverse aperture l1.

From the foregoing it will be apparent to those skilled in the art that the illustrated embodiment of my invention provides a new and improved electrical connection meansyreadily and con-.

veniently constructed and assembled, and accordingly, accomplishes at least the principal object of my invention. On the other hand, it also will be obvious to those skilled in the art that the illustrated embodiment of my invention may be variously changed and modified, or features thereof, singly or collectively, embodied in other combinations than those illustrated, without departing from the spirit of my invention, or sacrificing all of the advantages thereof, and that accordingly, the disclosure herein is illustrative only, and my invention is not limited thereto.

I claim: 4

l. A terminal post, comprising: an elongated solid metal body, having its lower end adapted to be secured to a support, and being provided with a transverse aperture intermediate its ends for receiving a snap-type plug conductor terminal, said body at its free end being of conical formation and tapered to a smaller diameter at its extremity, and having a longitudinal bore extending inwardly from said free extremity, the size of the bore being such that the marginal defining surface of said body adjacent its free end is reduced to a thin bendable condition, and said body having a second smaller longitudinal bore axially aligned With said first bore, forming a shoulder between said first and second bores, and establishing communication between said first bore and said transverse aperture; a detent member, disposed within said body, comprising a circular flange of a size to closely but freely fit within said first bore, and a rounded projection extending from one side of said flange and freely extending through said second bore, and an elongated shank extending fromv the opposite side of said flange and disposed Within said first bore; a helical spring disposed about said shank;

said free extremity of said body having defining walls of tapering cross-section bent annularly inwardly to provide an interior trough against which one end of said spring abuts, the other end of said spring abutting said opposite side of said flange, and urging said one side of said flange to abutment with said shoulder, and urging also said rounded projection into position to electrically engage in snap-relation with a plug conductor terminal disposed with said transverse aperture. a

2. A terminal post, comprising: an elongated solid metal body, having its lower end adapted to be secured to a support, and being provided with a transverse aperture intermediate its ends for receiving a snap-type plug conductor terminal, said body at its free end being of conical formation and tapered to a smaller diameter at its extremity, and having a longitudinal bore extending inwardly from said free extremity, the size of the bore being such that the marginal defining surface of said body adjacent its free end is reduced to a thin bendable condition, and said body having a second smaller longitudinal bore axially aligned with said first bore, forming a shoulder between said first and second bores, and establishing communication between said first bore and said transverse aperture; a detent member, disposed within said body, comprising a circular flange of a size to closely but freely fit within said first bore, and a rounded projection extending from one side of said flange and freely extending through said second bore, and an elongated shank extending from the opposite side of said flange and disposed within said first bore; a helical spring, the inner peripheral surface of the coils of said spring closely but slidably fitting about said shank, one end of said spring abutting said opposite side of said flange, and the other end of said spring being positioned adjacent said free extremity of said'body; said free extremity having defining walls of tapering cross-section bent annularly into the space defined by the inner periphery of the adjacent coils of said spring said adjacent end of said spring bearing against said bent extremity, and said one end of said spring urging said one side of saidflange to abutment with said shoulder, and urging also said rounded projection into position to electrically engage in snap-relation with a plug conductor terminal disposed with said transverse aperture.

HARRY A. DOUGLAS 

